The 79-year-old Mexican billionaire controls America Movil, the largest mobile-phone operator in Latin America, and holds stakes in several other publicly traded companies, including The New York Times.

He also has holdings in banking and mining ...

... as well as interests in the construction industry in Mexico through the family's business, infrastructure, construction, and energy conglomerate, Grupo Carso. Slim's son, Carlos Slim Domit, is now chairman of the board at Grupo Carso.

Carlos Slim speaks with his son and Chairman of the Board of Directors of Grupo Carso, Carlos Slim Domit, in Mexico City in February 2018.REUTERS/Edgard Garrido

Slim holds a deep love for his country. "Mexico is so rich in culture and history, and I have always enjoyed that," he told the Telegraph.

Slim went to college at Universidad Nacional Autonoma de Mexico, or UNAM, Mexico's National Autonomous University. He studied civil engineering and graduated in 1961. Soon after, he founded his first company, Inversora Bursatil, an insurance company.

Though Slim is known best as the chief shareholder of America Movil and the founder of the Grupo Carso conglomerate, his riches also result from many other business ventures. Slim spent much of the '60s, '70s, and '80s building a diverse portfolio that now dominates the Mexican economy.

Slim has a foolproof strategy for making money: He acquires struggling companies and transforms them into multibillion-dollar holdings before selling his stake at a profit. In particular, he took advantage of the Mexican debt crisis in 1982 in order to purchase many deflated companies.

We saw Slim's strategy firsthand in the US in 2009, when he loaned $250 million to The New York Times at a 14% interest rate. Slim saw the deal as a business venture, rather than a foray into journalism.

But Slim announced in 2017 that he would sell almost half his shares by 2020 and in 2018 alone, he sold at least $86 million worth of his shares.

Slim first entered the international spotlight in 1991 when he appeared on Forbes' billionaires list with a net worth of $1.7 billion. The previous year, he saw his first big success when Grupo Carso went public and led the privatization of state phone company Telmex.

In 2010, Slim surpassed Bill Gates as the richest man in the world; it was the first time in 16 years that the world's richest man wasn't from the US. Though Bill Gates is once again richer than Slim and Jeff Bezos reigns as the world's richest person, Slim is the wealthiest person in Mexico by far.

The next-richest person in Mexico is Ricardo Salinas, worth $10.7 billion, who owns the majority of two publicly traded companies: Grupo Elektra, a retail and banking conglomerate, and TV Azteca, a Spanish-language broadcaster.

Ricardo Salinas is the second-richest person in Mexico.ERIC PIERMONT/AFP/Getty Images

Slim's presence is all over Mexico. As The Guardian reported, "It is sometimes hard to tell where Carlos Slim stops and Mexico City starts. He controls most of the mobile phone, landline and internet markets. His telecoms company, Telmex, installed the city’s surveillance cameras. Grupo Carso, his flagship infrastructure conglomerate, runs the city’s principal water treatment plant. His bank, Inbursa, is Mexico's. He even owns the city’s only aquarium."

Slim's critics accuse him of being a monopolist whose practices drive prices and unemployment through the roof. The billionaire doesn't let criticism bother him: "When you live for others' opinions, you are dead," he said. "I don't want to live thinking about how I'll be remembered."

In fact, Slim has no need to cater to public opinion; his wealth has granted him political influence to the extent that, for the most part, the Mexican government turns a blind eye to the dominance he has over the telecom industry.

Despite his critics, Slim states that since becoming a billionaire, he has "more activity, more responsibility, and more compromise … The compromise is the challenge of solving Mexico's problems. I’m trying to make our country better in the areas that I can."

Slim says one of his biggest goals is alleviating poverty, and that it needs to happen at the institutional level. "Poverty isn’t solved with donations," he said. "The establishment of business is more beneficial to society than going around like Santa Claus."

Despite his wealth, Slim does not believe in conspicuous consumption — he reportedly doesn't own any yachts or planes. Most of his money goes towards further investments in business or philanthropy, though he does have a set of hand-carved and blown Baccarat wine glasses that were owned by the previous president of Mexico.

Tim Padgett, who interviewed Slim for Time magazine, said, "Just by looking at him, you would never know he is a billionaire." Slim has lived in the same six-bedroom house for 40 years. He indulges in only two big luxuries: Cuban cigars and art collecting.

Slim's home, his childhood home, and the Telmex offices are all located in Lomas de Chapultepec, a small but affluent neighborhood in Mexico City's financial district.Google Earth

Slim was married to his wife, Soumaya, for 32 years. She passed away in 1999 due to renal failure. The couple has six children, who will inherit Slim's empire.

In 1994, Slim opened the Museo Soumaya, a nonprofit art museum with free admission in Mexico City named after his late wife, Soumaya. At one point, it housed the largest private Rodin collection in the world.

After his wife's death, rumors circulated of Slim's subsequent romances, most famously with Queen Noor al-Hussein of Jordan. Both Soumaya and Queen Noor's husband, King Hussein, passed away within one day of one another in 1999. Ten years later, newspaper outlets reported that Slim and the Queen of Jordan had formed a close relationship that included jet-setting around the globe and dining in secret at friends' houses.

Since 2004, Slim has stepped down from the boards of his three largest companies in order to focus on family, philanthropy, and his own health. Every Monday he has dinner with his children and their spouses to discuss business, and every Wednesday he has lunch with his grandchildren.

Carlos Slim and his family seen in May 2015 in Oviedo, Spain.Europa Press/Europa Press via Getty Images

Slim still maintains ultimate control of his companies, but he has handed over much of the responsibility and decision-making to his three sons, Carlos, Marco Antonio, and Patrick, and to his son-in-law, Arturo Elías Ayub.